Chalk Render

The Chalk Render option is used to create a simple form study of your scene.

guggenheimSU

guggenheim50m

SketchUp Model of Guggenheim Museum, Bilbao

Shaderlight Chalk Rendered Form Study

There is NO LIGHT in a Chalk Render image; a white material is applied to all of your model and shadows are created when one surface is close to another. The closer surfaces are to one another (for example where the wall meets the floor), the darker the shadow becomes. Adding artificial lights to the scene will make no difference.


SketchUp surfaces get closer into the corner	Chalk Render shadows get darker into the corner

Shadow Range

The range over which one surface can shadow another is controlled by the Shadow Range. The Shadow Range is in scene units and marks the distance from an object where the shadow fades away to white. In the example below the blocks are 1 meter cubes and the lines on the wall and floor are 1 meter apart.

chalkBlocks01m

chalkBlocks02m

chalkBlocks03m

Shadow Range = 1 meter

Shadow Range = 2 meters

Shadow Range = 3 meters

When the Shadow Range is only 1 meter, the only shadow on the wall is within 1 meter of the floor. With a Shadow Range of 2 meters, the first block creates a shadow on the wall because it is only 1 meter away, but the other two blocks have no effect. With a Shadow Range of 3 meters, there's quite a dark shadow behind the first block and a slight shadow behind the second.

Notice also that the shadow created by the blocks on the floor grows further away from the base of the blocks as the shadow range goes up.

On a bigger scene, the value of the shadow range may need to be much larger. The Guggenheim Museum model is full scale, so for an acceptable form study the range required could be as high as 100 meters.

guggenheim01m

guggenheim10m

guggenheim100m

Shadow Range = 1 meter

Shadow Range = 10 meters

Shadow Range = 100 meters

Chalk Render Backgrounds

The background options for a Chalk Render allow you to use the SketchUp Background, the Lighting Environment (which renders as a 50% grey background) and a Custom background. Note that if Shadows are turned on in SketchUp, the ground plane will be rendered white to the horizon.

chalkBackgroundSU

chalkBackground

chalkBackgroundCustom

SketchUp Background

Lighting Environment Background

Custom Background

Tip: Because the Chalk Render is predominantly white, using a white SketchUp background gives pleasing results. Edit the Background color using the SketchUp Styles window